Information processing device, image system, and method of transferring data

ABSTRACT

An information processing device includes a first input interface to receive data transferred in a first transfer mode in which a plurality of elements of the data each belonging to a same line of a plurality of lines are transferred in parallel, a second input interface to receive data transferred in a second transfer mode in which a plurality of elements of the data each belonging to a corresponding one of the plurality of lines are transferred in parallel, a mode selection circuit to change a transfer mode of the data from the second input interface from the second transfer mode to the first transfer mode based on a signal indicating selection of the second input interface, and an output interface to output one of the data from the first input interface and the data from the second input interface.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application is based on and claims priority pursuant to 35U.S.C. § 119(a) to Japanese Patent Application No. 2016-044518, filed onMar. 8, 2016, in the Japan Patent Office, the entire disclosure of whichis hereby incorporated by reference herein.

BACKGROUND

Technical Field

Embodiments of the present disclosure relate to an informationprocessing device, an imaging system, and a method of transferring data.

Description of the Related Art

In a conventional electrophotographic imaging system, an imaging device,such as a complementary metal oxide semiconductor (COMS) sensor,typically transfers data in synchronization with a line synchronizationsignal to an arithmetic processing device, such as a digital signalprocessor (DSP). The imaging device may perform image processingincluding encoding the image data using software programs executed by acentral processing unit (CPU).

In recent years, a technique for performing the image processing,including encoding the data, with hardware before transferring to theDSP has been devised and employed.

Regarding the technique for performing the image processing, includingencoding the data with the hardware, a system in which the imagingdevice inputs the data to a hardware device that processes images andthen transfers the image data to the arithmetic processing device isknown. With this technique, which performs image processing in thehardware device before transferring the image data to the arithmeticprocessing device, the arithmetic processing device can process theimage without deterioration of performance.

In the conventional system, which uses the hardware device disposedbetween the imaging device and the arithmetic processing device toperform the image processing, the data output from the imaging device inunits of single lines is also input to the arithmetic processing devicein units of single lines. The arithmetic processing device thenprocesses the data in units of lines. Alternatively, there is also knownan imaging device that transfers multiple lines at a time. Such animaging device can perform complicated image processing by processingmultiple lines simultaneously.

SUMMARY

An information processing device includes a first input interface toreceive data transferred in a first transfer mode in which a pluralityof elements of the data each belonging to a same line of a plurality oflines are transferred in parallel, a second input interface to receivedata transferred in a second transfer mode in which a plurality ofelements of the data each belonging to a corresponding one of theplurality of lines are transferred in parallel, a mode selection circuitto change a transfer mode of the data from the second input interfacefrom the second transfer mode to the first transfer mode based on asignal indicating selection of the second input interface, and an outputinterface to output one of the data from the first input interface andthe data from the second input interface. The data from the second inputinterface is output after the transfer mode is changed to the firsttransfer mode.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendantadvantages and features thereof can be readily obtained and understoodfrom the following detailed description with reference to theaccompanying drawings;

FIG. 1 is a block diagram illustrating an imaging system according to anembodiment;

FIG. 2A is a diagram illustrating a data structure of image datagenerated with an image sensor;

FIG. 2B is a diagram illustrating a pattern of data alignment of theimage data transferred from an image sensor for image capturing;

FIG. 2C is a diagram illustrating a pattern of data alignment of theimage data transferred from an image sensor for automatic exposure (AE);

FIG. 3 is a block diagram illustrating a hardware configuration of animage transfer mode selection circuit in the imaging system illustratedin FIG. 1;

FIGS. 4A, 4B, and 4C are timing charts illustrating states of the databeing input to and output from the image transfer mode selectioncircuit;

FIG. 5 is a block diagram illustrating a hardware configuration of aselector in the imaging system according to the embodiment;

FIG. 6A is a diagram illustrating mirror operation and data transfer;

FIG. 6B is a diagram illustrating state transition of the imaging systemaccording to the embodiment; and

FIG. 7 is a block diagram illustrating an imaging system according toanother embodiment.

DETAILED DESCRIPTION

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentdisclosure. As used herein, the singular forms “a”, “an” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“includes” and/or “including”, when used in this specification, specifythe presence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

In describing preferred embodiments illustrated in the drawings,specific terminology is employed for the sake of clarity. However, thedisclosure of this patent specification is not intended to be limited tothe specific terminology so selected, and it is to be understood thateach specific element includes all technical equivalents that have thesame function, operate in a similar manner, and achieve a similarresult. In the embodiment described below, an image processing engine108 and an imaging system 100 including the image processing engine 108are respectively described as one of examples of an informationprocessing device and an imaging system.

FIG. 1 is a block diagram illustrating the imaging system 100 accordingto one of embodiments. The imaging system 100 includes the imageprocessing engine 108. The imaging system 100 illustrated in FIG. 1includes a plurality of image sensors 102, an arithmetic processingdevice 104, and the image processing engine 108. The image processingengine 108 is connected to the plurality of image sensors 102, thearithmetic processing device 104, and a mirror mechanism 106.

The image sensor 102 transfers image data in units of lines through afirst differential serial bus 122 based on synchronization signals 120including a frame synchronization signal and a line synchronizationsignal (hereinafter, both of the frame synchronization signal and theline synchronization signal are collectively indicated with a numeralreference of 120) received from the arithmetic processing device 104. Inthe description of the embodiment, two image sensors 102 are provided.As an example of the embodiment, one of the two image sensors 102 is animage sensor 102A that is used for capturing an image (hereinafter theimage sensor 102B may be referred to as an image capturing-image sensor102A), and the other is an image sensor 102B that is used for automaticexposure (AE) (hereinafter, the image sensor 102B may be referred to asan AE image sensor 102B. As one example of the first differential serialbus 122, low voltage differential signaling (LVDS) may be used. Each ofthe first differential serial buses 122 may have two or more lanes. Herein the embodiment, each differential serial bus 122 has two lanes. Usingthe first differential serial bus 122 improves noise resistance intransferring data from the image sensor 102 to the image processingengine 108.

The arithmetic processing device 104 includes a digital signal processor(DSP). The arithmetic processing device 104 outputs the framesynchronization signal and the line synchronization signal 120 to eachof the plurality of image sensors 102. The arithmetic processing device104, which is placed in the latter-stage of the image processing engine108, processes the image data transferred from the image sensor 102 viathe image processing engine 108.

The mirror mechanism 106 is a mechanism that is employed in, forexample, a single-lens reflex camera. The mirror mechanism 106 has aplurality of states that indicate which one of the plurality imagesensors 102 an image reaches to after passing through a lens. In theembodiment, the mirror mechanism 106 has a first state (open) in whichthe image passes through the lens and reaches the image sensor 102A,which is used for image capturing, and a second state (close) in whichthe image passes through the lens and reaches to the image sensor 102B,which is used for AE. The mirror mechanism 106 inputs a status signal130 to the image processing engine 108 to give information on the stateof the mirror mechanism 106 to the image processing engine 108. Thestatus signal 130 reflects one of the first state (open) indicatingselection of an image sensor 102A side, which is used for imagecapturing, and the second state (close) indicating selection of an imagesensor 102B side, which is used for AE.

The image processing engine 108 performs a predetermined processing onthe image data transferred from the image sensors 102 based on thestatus signal 130, and then transfers the image data to the arithmeticprocessing device 104 through a second differential serial bus 128. Asone example of the second differential serial bus 128, the LVDS may beused. The differential serial bus 128 has two or more lanes. In theembodiment, the second differential serial bus 128 has two lanes. Usingthe second differential serial bus 128 improves the noise resistance intransferring the data from the image processing engine 108 to thearithmetic processing device 104.

FIG. 1 also illustrates a detailed configuration of the image processingengine 108. The image processing engine 108 illustrated in FIG. 1includes a plurality of interface controllers 110 placed in an inputside, a plurality of image processors 112, a selector 114, an imagetransfer mode selection circuit 116, and an interface controller 118placed in an output side. In the embodiment, two interface controllers110A and 110B and two image processors 112A and 112B are provided tocorrespond to the number of image sensors 102.

The interface controllers 110A and 110B individually control aninterface, such as a LVDS interface. Each of the interface controllers110A and 110B generates a line synchronization signal, a frame validsignal, and a line valid signal based on image area informationtransferred through the corresponding one of the differential serialbuses 122A and 122B. The image area information includes synchronizationinformation that defines a frame and lines. The line synchronizationsignal indicates a start of a line. The frame valid signal indicates astart of a frame. The line valid signal indicates that output pixels ofdata are valid. Three signals of the line synchronization signal, theframe valid signal, and the line valid signal are configured as timingcontrol signals in the embodiment, and hereinafter may collectivelyreferred to as control signal 126A and 126B.

The interface controllers 110A and 110B receive the image datatransferred from the differential serial buses 122A and 122B,respectively, at the same time, and then output the image data, as datato be processed in the image processing engine 108, to the data buses124A and 124B, respectively. Each of the data buses 124A and 124B hastwo lanes each of which sends the image data pixel by pixel.

Each of the image sensors 102A and 102B, which are placed in the inputside of the image processing engine 108, outputs the image data to thecorresponding one of the interface controllers 110A and 110B through thecorresponding one of the differential serial buses 122A and 122B, in apredetermined transfer mode. As described above, each of thedifferential serial buses 122A and 122B has a plurality of lanes. Forexample, the image capturing-image sensor 102A transfers a plurality ofpixels each belonging to the same line in parallel, using the pluralityof lanes. Hereinafter, this transfer mode, which is used in the imagesensor 102A side, is referred to as a multi-pixel parallel transfermode. The AE image sensor 102B, for example, transfers the plurality ofpixels each belonging to a corresponding one of the plurality of linesin parallel using the plurality of lanes. Hereinafter, this transfermode, which is used in the AE image sensor 102B side, is referred to asa multi-line parallel transfer.

In the embodiment, each of the first differential serial buses 122A and122B has two lanes. In the embodiment, the image capturing-image sensor102A, accordingly, transfers two pixels both belonging to the same linein parallel, and namely uses a two-pixel parallel transfer mode. Inaddition, the AE image sensor 102B, accordingly, uses a two-lineparallel transfer mode in which two pixels each belonging to acorresponding one of two different lines are transferred in parallel.The present disclosure, however, is not limited to the embodimentdescribed above, and as another embodiment, the image sensor 102 may usea transfer mode in which three or more arbitrary pixels or three or morepixels in an arbitrary line are transferred in parallel according to thenumber of lanes of the first differential serial bus 122.

FIG. 2A is a diagram illustrating a data structure of the image datagenerated with the image sensor 102 according to the embodiment. Asdescribed in FIG. 2A, the image sensor 102 has a plurality of imagingelements, such as photodetectors, arranged in an X-Y matrix, with eachimaging element usually corresponding to one pixel of the image data.The image sensor 102 resets a counter at a transfer position in thefirst line in response to the frame synchronization signal, andtransfers pixels sequentially from the first pixel in each line everytime the line synchronization signal is input. With the multi-pixelparallel transfer mode, the plurality of pixels that belongs to the sameline and has the same number with the number of lanes are transferred inparallel, when there are the plurality of lanes. With the multi-lineparallel transfer mode, the number of lines corresponding to the numberof lanes are transferred in parallel.

FIG. 2B is a diagram illustrating a pattern of data alignment of theimage data transferred from the image capturing-image sensor 102A. FIG.2C is a diagram illustrating a pattern of data alignment of the imagedata transferred from the AE image sensor 102B. In FIGS. 2B and 2C, thenumber of lanes is two.

As described above, the image capturing-image sensor 102A transfers theimage data in the two-pixel parallel transfer mode. In the two-pixelparallel transfer mode, the pixels of data sequentially positioned inthe same line are transferred sequentially using the two lanes, lane 1and lane 2, in synchronization with the line synchronization signal fromthe arithmetic processing device 104, after the frame synchronizationsignal is input from the arithmetic processing device 104. That is,arrangement of transfer data is illustrated as an data array 210 of FIG.2B, in which a set of odd-numbered pixels in the same line istransferred using one of the two lanes (lane 1) and a set ofeven-numbered pixels in the same line is transferred using the other ofthe two lanes (lane 2).

The AE image sensor 102B transfers the image data in the two-lineparallel transfer mode. In the two-line parallel transfer mode, eachline of data is transferred using one of two lanes pixel by pixel, sothat two lines of data is transferred at a time using lane 1 and lane 2in a pixel basis in synchronization with the line valid signal from thearithmetic processing device 104, after the frame synchronization signalis input from the arithmetic processing device 104. That is, thearrangement of transfer data is illustrated as a data array 220 of FIG.2B, in which the pixels in the same line are transferred using one ofthe two lanes.

Here in the description with reference to FIGS. 2B and 2C, two pixelsare illustrated as simultaneously sent with two lanes, however, twopixels may not sent strictly at the same time, but may sent almost atthe same time.

The image capturing-image sensor 102A transfers the image data in themulti-pixel parallel transfer mode as described above. The interfacecontroller 110A in the embodiment, accordingly, serves as a first inputfunction that receives transfer data in which a plurality of elements inthe same line are transferred in parallel. The AE image sensor 102Btransfers the image data in the multi-line parallel transfer mode asdescribed above. The interface controller 110B in the embodiment,accordingly, serves as a second input function that receives thetransfer data in which elements each belonging to different one of theplurality of lines are transferred in parallel.

Additionally, the arithmetic processing device 104 placed in the outputside of the image processing engine 108 typically receives the imagedata transferred in the multi-pixel parallel transfer mode. The imageprocessing engine 108, accordingly, changes a transfer mode of the imagedata output in the multi-line parallel transfer mode from the AE imagesensor 102B to the multi-pixel parallel transfer mode, which is usedwith the image capturing-image sensor 102A, and then transfers the imagedata to the arithmetic processing device 104.

Returning to FIG. 1, the detailed configuration of the image processingengine 108 is described more below. The interface controllers 110A and110B generate the image data and the control signals and transfer to theimage processors 112A and 112B, respectively. The image processors 112Aand 112B perform image processing, including encoding, on the receivedimage data. The image processors 112A and 112B each can detect an imagearea based on the control signal generated based on the image areainformation at the interface controllers 110A and 110B. By detecting theimage area, the image processors 112A and 112B can process the imagedata efficiently. Additionally, the image processor 112B receives theimage data transferred in the multi-line transfer mode from the AE imagesensor 102B and processes the plurality of lines of data at a time, andthus achieves more complicated image processing than simple imageprocessing that is performed in line by line.

The selector 114 selects the image data and the control signal from oneof the image capturing-image sensor 102A and the AE image sensor 102B,and then outputs the selected image data and control signal to the imagetransfer mode selection circuit 116, which is placed in thelatter-stage. In the description of the embodiment, the selector 114selects a data path based on the status signal 130 from the mirrormechanism 106. The selector 114 selects the data path that is from theinterface controller 110A of the image capturing-image sensor 102A sideto the interface controller 118, when the status signal 130 indicatesthe selection of the image capturing-image sensor 102A side. At the sametime, the selector 114 selects the data path that is from the interfacecontroller 110B of the AE image sensor 102B side to the interfacecontroller 118, when the status signal 130 indicates the selection ofthe AE image sensor 102B side. The selector 114 serves as a selectingfunction in the embodiment.

The image transfer mode selection circuit 116 selects one of themulti-pixel parallel transfer mode from the image capturing-image sensor102A and the multi-line parallel transfer mode from the AE image sensor102B based on the status signal 130 from the mirror mechanism 106.

In the description of the embodiment, the image transfer mode selectioncircuit 116 changes transfer mode of the image data and the controlsignal from the multi-line parallel transfer mode into the multi-pixelparallel transfer mode, when the status signal 130 indicates theselection of the AE image sensor 102B side (the status signal 130indicates the second status (close)). The image transfer mode selectioncircuit 116 then outputs the image data and the control signal to theinterface controller 118 placed in the latter-stage. The image transfermode selection circuit 116 serves as a mode changing function in theembodiment.

As described above, the image data and the control signal aretransferred from the interface controllers 110A and 110B to theinterface controller 118. The interface controller 118 generates imagearea information based on the control signal input from the pre-stage.The interface controller 118 then outputs, to the arithmetic processingdevice 104, which is placed in the latter-stage, the image data from theimage capturing-image sensor 102A or the image data of which thetransfer mode is changed with the image transfer mode selection circuit116, in the multi-pixel parallel transfer mode through the seconddifferential serial bus 128. The interface controller 118 serves as anoutputting function in the embodiment.

A detailed configuration of the image transfer mode selection circuit116 will be described with reference to FIGS. 3 and 4. FIG. 3 is a blockdiagram illustrating a hardware configuration of the image transfer modeselection circuit 116 of the imaging system 100 according to theembodiment. The image transfer mode selection circuit 116 illustrated inFIG. 3 includes a pixel position changing unit 132, a line buffercontrol unit 134, a line buffer 136, a line synchronization signalcontrol unit 138, a register control unit 140, and an image transfermode selecting unit 142.

The image transfer mode selection circuit 116 receives the controlsignals including a line synchronization signal 150, a frame validsignal 152, and a line valid signal 154 as an input from the selector114 in the pre-stage. The image transfer mode selection circuit 116 alsoreceives the transferred image data from the selector 114 of thepre-stage through data buses 156 and 158. The data buses 156 and 158each have a bus width corresponding to the number of bits per pixel. Inthe description of the embodiment, the image data and the control signalinput from the selector 114 in the pre-stage are from one of the imagesensors 102 selected with the selector 114.

The register control unit 140 holds control register setting values forvarious setting. The control register setting values include a settingvalue for changing the transfer mode. The number of pixels per line tobe transferred is hold in the register control unit 140. The settingvalue for changing the transfer mode indicates whether the transfer modeis changed based on the status signal 130, or the transfer mode is fixedregardless of the status signal 130. The register control unit 140outputs a select signal to the image transfer mode selecting unit 142based on the setting value for changing the transfer mode. Informationindicating the number of pixels per line to be transferred is informedto the line buffer control unit 134 via the image transfer modeselecting unit 142. Register setting of the register control unit 140 isperformed with, for example, a central processing unit (CPU) or thearithmetic processing device 104. The register control unit 140 servesas a setting function in the embodiment.

The image transfer mode selecting unit 142 generates a selection controlsignal to select an image transfer mode based on the select signal fromthe register control unit 140 and the status signal 130 from the mirrormechanism 106, and then outputs the selection control signal to thepixel position changing unit 132, the line buffer control unit 134, andthe line synchronization signal control unit 138.

The image transfer mode selecting unit 142 uses the select signal fromthe register control unit 140 to determine whether to automaticallycontrol the transfer mode based on the status signal 130 or to selectthe transfer mode based on the control setting value.

For example, when the select signal has two bits, “00” may indicate stopof data transfer, “01” may indicate automatic control, “10” may indicatethe two-pixel parallel transfer mode, and “11” may indicate the two-lineparallel transfer mode. With this definitions of the select signalhaving two bits, when the select signal indicates the automatic control(“01”), the image transfer mode selecting unit 142 generates theselection control signal that indicates and sets whether to change thetransfer mode based on the status signal 130 that is further input tothe image transfer mode selecting unit 142. When the select signalindicates the two-pixel parallel transfer mode (“10”), the imagetransfer mode selecting unit 142 generates the selection control signalthat indicates and sets not to change the transfer mode regardless ofthe status signal 130 input. When the select signal indicates thetwo-line parallel transfer mode (“11”), the image transfer modeselecting unit 142 generates the selection control signal that indicatesand sets to change the transfer mode regardless of the status signal 130input. When the select signal indicates the stop of the data transfer(“00”), the control signal that indicates to stop of the data transferis generated. As described above, an automatic control function for thetransfer mode can be activated or inactivated and thus the system havinghigh versatility can be achieved.

The pixel position changing unit 132, the line buffer control unit 134,and the line synchronization signal control unit 138 use the selectioncontrol signal from the image transfer mode selecting unit 142 to stopor start the data transfer.

Based on the selection control signal from the image transfer modeselecting unit 142, the pixel position changing unit 132 stores theimage data, which is transferred from the selector 114, to the linebuffer 136 according to the line synchronization signal 150, the framevalid signal 152, and the line valid signal 154.

As long as the status signal 130 indicating the selection of the imagecapturing-image sensor 102A side (open) is input under the automaticcontrol, the selection control signal that indicates not to change thetransfer mode is input to the pixel position changing unit 132. When thetransfer mode is not to be changed, the transfer mode is the two-pixelparallel transfer mode, and the pixel position changing unit 132requests the line buffer 136 to write the data to in units of twopixels. In contrast, as long as the status signal 130 indicating theselection of the AE image sensor 102B side (close) is input under theautomatic control, the selection control signal that indicates to changethe transfer mode is input to the pixel position changing unit 132 isinput. When the transfer mode is to be changed, the present transfermode is the multi-line parallel transfer mode, and the pixel positionchanging unit 132 requests each line buffer to write the data pixel bypixel. The pixel position changing unit 132 serves as a storing functionin the embodiment.

The line buffer 136 stores the plurality of lines of data. The linebuffer 136 can process a write request from the pixel position changingunit 132 and a read request from the line buffer control unit 134concurrently. The line buffer 136 saves the image data in a manner thatthe pixels in the same line are arranged sequentially. The system usingthe two-line parallel transfer mode defines two lines as a set, andwrites and reads by toggle-switching between two sets.

The line synchronization signal control unit 138 generates a pseudo linesynchronization signal 160 and a frame valid signal 162 output to thelatter-stage based on the line synchronization signal 150 and the framevalid signal 152 transferred from the pre-stage and the selectioncontrol signal input from the image transfer mode selecting unit 142.

As long as the status signal 130 indicating the selection of the AEimage sensor 102B side (close) is input, in particular, under theautomatic control, the selection control signal that indicates to changethe transfer mode is input to the line synchronization signal controlunit 138. When the transfer mode is to be changed, the linesynchronization signal control unit 138 measures a cycle of the linesynchronization signal from the AE image sensor 102B side, and generatesa pseudo line synchronization signal 160 having a pseudo line cycle anda frame valid signal 162 synchronized with the pseudo linesynchronization signal 160 based on the measured cycles. The pseudo linecycle may have a cycle corresponding to one of the number of lanes inthe measured cycle. In the description of the embodiment, the number oflanes is two, so that the pseudo line synchronization signal 160 havinga half cycle of the measured cycle is generated.

Generating the pseudo line synchronization signal 411 allows an outputmode to be switched to a pixel-parallel transfer mode when an input modeis a line-parallel transfer mode.

When the transfer mode is not to be changed, the line synchronizationsignal control unit 138 generates the pseudo line synchronization signal160 and the frame valid signal 162 at a timing of the linesynchronization signal from the image capturing-image sensor 102A sidein the cycle as it is. The line synchronization signal control unit 138serves as a signal generating function in the embodiment.

The line buffer control unit 134 reads the plurality of pixels in thesame line from the line buffer 136 based on the pseudo linesynchronization signal 160 and the frame valid signal 162 from the linesynchronization signal control unit 138. The line buffer control unit134 then transfers the image data with the line valid signal 164synchronized with the pseudo line synchronization signal 160 to thelatter-stage through data buses 166 and 168. The line buffer controlunit 134 reads out the plurality of pixels in the same line stored inthe line buffer 136 no matter what indication, to change the transfermode or not to change the transfer mode, the selection control signalindicates, and transfers the image data read from the pre-stage to thelatter-stage in the two-pixel parallel transfer mode.

The line buffer control unit 134 serves as a transferring function inthe embodiment.

The image transfer mode selection circuit 116 outputs the pseudo linesynchronization signal 160, the frame valid signal 162, and the linevalid signal 164 that are controlled with the selection control signalfrom the image transfer mode selecting unit 142 to the interfacecontroller 118 placed in the latter-stage. The image transfer modeselection circuit 116 further transfers the image data to the interfacecontroller 118 in the latter-stage through the data buses 166 and 168.The data buses 166 and 168 individually output the plurality of pixelsconcurrently in synchronization with the pseudo line synchronizationsignal. The data buses 166 and 168 individually have a bus widthcorresponding to the number of bits per pixel. The pseudo linesynchronization signal 160 serves as a trigger for transferring the datato the second differential serial bus 128. Each of the frame validsignal 162 and the line valid signal 164 can define an amount oftransfer data and thus the efficient data transfer can be achieved.

In a preferable example of the embodiment, the image transfer modeselection circuit 116 can control the transfer of the image data to thelatter-stage based on one or both of states of the frame valid signals,one from the image capturing-image sensor 102A side and the other fromthe AE image sensor 102B side, when detecting the state of the statussignal 130 is switched.

In the preferable example of the embodiment, the image transfer modeselecting unit 142, more specifically, can determine the selectioncontrol signal, which is sent to each of the pixel position changingunit 132, the line buffer control unit 134, and the line synchronizationsignal control unit 138, based on the state of the frame valid signal162. For example, when the state of the status signal 130 is switched ina middle of transferring frame data, the image transfer mode selectingunit 142 can delay the switching of the control select signal until theframe valid signal 162 is negated. The negation of the frame validsignal 162 indicates that the frame data transfer is completed, so thatthe frame data is maintained even when the state of the status signal130 is switched in the middle of the frame data transfer. That is,occurrence of an abnormal image data is prevented from by switching adata path after the completion of the frame data transfer.

The line synchronization signal control unit 138 further can stop thetransfer until detecting the frame valid signal 162 is asserted nexttime when a switched destination of the transfer is in a middle of theframe data transfer. This is because that the AE image sensor 102B maycontinuously input the frame data for transferring a frame as the framedata, though the image capturing-image sensor 102A transfers a frame asthe frame data at a time. One or both of the image transfer modeselecting unit 142 and the line synchronization signal control unit 138serves as a mode change controlling function in the preferable exampleof the embodiment.

FIGS. 4A to 4C are timing charts each illustrating input and output ofthe image transfer mode selection circuit 116 in the imaging system 100.Operation in transferring the image data in the two-line paralleltransfer mode from the AE image sensor 102B is described with referenceto FIGS. 4A to 4C. FIG. 4A is the timing chart illustrating the inputand output of the image transfer mode selection circuit 116 in an inputside. FIGS. 4B and 4C are the timing charts illustrating the input andoutput of the image transfer mode selection circuit 116 in an outputside. FIG. 4B illustrates operation in association with a start of animage area. FIG. 4C illustrates operation in association with an end ofthe image area. A V blank period in FIGS. 4B and 4C is a period for ablank area, which is not the image area.

Under the automatic control, when the status signal 130 is switched toindicate the selection of the AE image sensor 102B side (close), theimage data and the control signal received at the interface controller110B are input to the image transfer mode selection circuit 116 in thetwo-line parallel transfer mode.

When the status signal 130 indicating the selection of the AE imagesensor 102B side (close) is input, the image transfer mode selectingunit 142 outputs the selection control signal that indicates to changethe transfer mode to the line synchronization signal control unit 138,pixel position changing unit 132, and the line buffer control unit 134.

The operation of the line synchronization signal control unit 138 isdescribed with reference to FIGS. 4A to 4C. When the transfer mode is tobe changed, the line synchronization signal control unit 138 startsmeasuring an assert cycle of the line synchronization signal 150 at atime when the frame valid signal 152 is asserted.

At the start of the image area, when the frame valid signal 152 isnegated, the pseudo line synchronization signal 160 is asserted with anassertion timing of the line synchronization signal 150, as described inFIG. 4B. On the other hand, when the frame valid signal 152 is asserted,the pseudo line synchronization signal 160 is asserted with a timing ofthe pseudo line synchronization cycle that has a half cycle of themeasured cycle. Every time the line synchronization signal 150 isasserted, a pseudo line cycle issuing counter is reset, and the pseudoline cycle can synchronize for each two lines.

At the end of the image area, when the frame valid signal 152 isnegated, the pseudo line synchronization signal 160 stops asserting withthe timing of the pseudo line synchronization cycle, and is assertedonly with an assertion timing of the line synchronization signal 150, asdescribed in FIG. 4C. As described above, stopping generating the pseudoline synchronization signal with the pseudo line cycle after the end ofthe image area and returning the assertion cycle of the pseudo linesynchronization signal 160 can prevents the interface controller 118placed in the latter-stage from issuing unnecessary unnecessary linesynchronization packets. This further can reduce power consumption.

Next, the operations of the pixel position changing unit 132 and theline buffer control unit 134 are explained with reference to FIGS. 4A to4C. The pixel position changing unit 132 requests the line buffer 136 towrite for each of data buses 166 and 168, when being input the selectioncontrol signal indicating that the transfer mode is to be changed. Theline buffer control unit 134 requests the line buffer 136 to read twopixels at a time for each line, and transfers the image data to the databuses 166 and 168 in the two-pixel parallel transfer mode. As describedabove, the register control unit 140 holds the control register settingvalue for setting the number of pixels for each line, and the controlregister setting value is sent to the line buffer control unit 134 viathe image transfer mode selecting unit 142. The line buffer control unit134 performs read request for the number of pixels based on theinformation of the control register setting value, and stops readinguntil the pseudo line synchronization signal is asserted next time.

As described above, the transfer mode of the image data from the AEimage sensor 102B side can be changed in a manner that the plurality ofelements are transferred in parallel, and then the image data of whichthe transfer mode is changed can be output from the interface controller118.

Operation in transferring the image data from the image capturing-imagesensor 102A in the two-pixel parallel transfer mode is described below.

Under the automatic control, when the status signal 130 indicating theselection of the image capturing-image sensor 102A side (open) is input,the image data and the control signal input to the interface controller110A in the two-pixel parallel transfer mode are input to the imagetransfer mode selection circuit 116.

When the status signal 130 indicating the selection of the imagecapturing-image sensor 102A side (open), the image transfer modeselecting unit 142 outputs the selection control signal indicating thatthe transfer mode is not to be changed to the line synchronizationsignal control unit 138, the pixel position changing unit 132, and theline buffer control unit 134. When the transfer data is not to bechanged, the line synchronization signal control unit 138 does notmeasure the assert cycle of the line synchronization signal 150 norassert the line synchronization signal with the timing of the pseudoline cycle, but asserts the pseudo line synchronization signal 160 withthe assertion timing of the line synchronization signal 150.

The pixel position changing unit 132 requests the line buffer to writetwo pixels at a time in the two-pixel parallel transfer mode. At thistime, the line buffer 136 usually serving as a line buffer correspondingto four lines, serves as a line buffer corresponding to two lines. Thewrite request is performed as a write toggle operation in line by line.

The line buffer control unit 134 execute a read request that reads twopixels at a time for each line, even when the transfer mode is not to bechanged. The line buffer having the four lines is serving as the linebuffer for the two lines, so that the read request is performed in amanner that the two lines are toggle-switched to be read.

A detailed configuration of the selector 114 will be described withreference to FIG. 5. FIG. 5 is a block diagram illustrating the detailedconfiguration of the selector 114 in the imaging system 100 according tothe embodiment. The selector 114 illustrated in FIG. 5 includes aregister control unit 170, a data path selecting unit 172, and selectorunit 174.

The register control unit 170 holds control register setting values forvarious setting. As a control register setting value, a value associatedwith a selection for the data path may be hold. A setting valueassociated with the selection for the data path indicates whether thedata path is switched according to the status signal 130 or fixedregardless of the status signal 130. The register control unit 170outputs a select signal to the data path selecting unit 172 based on thesetting value associated with the selection for the data path. Registersetting of the register control unit 170 is performed with, for example,the central processing unit (CPU) or the arithmetic processing device104.

The data path selecting unit 172 generates and outputs a selectioncontrol signal to select a data path based on the select signal from theregister control unit 170 and the status signal 130 from the mirrormechanism 106.

The data path selecting unit 172 determines whether to select the datapath automatically according to the status signal 130 or notautomatically but based on the register setting value.

Similar to the image transfer mode selection circuit 116, for example,when the select signal has two bits, “00” may indicate the stop of datatransfer, “01” may indicate the automatic control, “10” may indicate thetwo-pixel parallel transfer mode (path for image capturing), and “11”may indicate the two-line parallel transfer mode (path for AE). Withthis definitions of the select signal having two bits, when the selectsignal indicates the automatic control (“01”), the data path selectingunit 172 generates the selection control signal that indicates theselection of one of the path for image capturing and the path for AE,based on status signal 130 that is further input to the data pathselecting unit 172. When the select signal indicates the path for imagecapturing (“10”), the data path selecting unit 172 generates theselection control signal that indicates the path for image capturingregardless of the status signal 130. When the select signal indicatesthe path for AE (“11”), the data path selecting unit 172 generates theselection control signal indicating the path for AE regardless of thestatus signal 130. When the select signal indicates the stop of the datatransfer (“00”), the control signal that indicates to stop of the datatransfer is generated.

The selector unit 174 controls to stop or start the data transfer byswitching the data path based on the control signal from the data pathselecting unit 172. The selector unit 174 selects the data path that isfrom the interface controller 110A to the interface controller 118 basedon the signal indicating the data path for image capturing. The selectorunit 174 selects the data path that is from the interface controller110B to the interface controller 118 based on the signal indicating thedata path for AE.

In a preferable embodiment, the selector 114 controls transfer of theimage data of the selected image path based on both or one of the framevalid signals 126-2A and 126-B respectively from the imagecapturing-image sensor 102A side and the image sensor for AE 202B sidewhen detecting switching of the status signal 130.

In the preferable example of the embodiment, the data path selectingunit 172, more specifically, can determine the selection control signal,which is sent to the selector unit 174, based on one or both of thestates of the frame valid signal which is presently selected (126-2A or126-2B) and the state of the frame valid signal of a switcheddestination (126-2B or 126-2A). For example, when the state of thestatus signal 130 is switched in a middle of transferring frame data,the data path selecting unit 172 can delay the switching of theselection control signal until the frame valid signal 162-2 for the sidepresently selected is negated. The negation of the frame valid signal126-2 indicates that the frame data transfer is completed, so that theframe data is maintained even when the state of the status signal 130 isswitched in the middle of the frame data transfer.

The data path selecting unit 172 further can stop the transfer untildetecting the frame valid signal 126-2 is asserted next time when aswitched destination of the transfer is in a middle of the frame datatransfer. The data path selecting unit 172 serves as a selectioncontrolling function in the preferable example of the embodiment.

Operation of switching based on the control register setting value andthe status signal 130 from the mirror mechanism 106 is described withreference to FIGS. 6A and 6B. FIG. 6A is a diagram illustrating mirroroperation and data transfer operation.

As described in FIG. 6A, in the mirror operation, HIGH indicates a firststate (open) in which an image from the lens reaches to the imagecapturing-image sensor 102A. On the other hand, LOW indicates a secondstate (close) in which the image from lens reaches to the AE imagesensor 102B. In FIG. 6A, shaded portions in image capturing operationand automatic exposer operation indicate light exposure periods. Incontrast, blank portions indicate data transfer periods. In the imagecapturing operation, light exposer and data transfer are individuallyperformed one time. In the automatic exposure operation, a plurality ofoperations are repeated and each operation includes the light exposureand the data transfer as same as the image capturing operation.

The data transfer in the automatic exposure operation is started whenthe mirror mechanism 106 detects that the mirror is closed and the datatransfer for the image capturing operation is completed. In contrast,the data transfer in the image capturing operation is started when themirror mechanism 106 detects that the mirror is opened and the datatransfer for the automatic exposer operation is completed.

FIG. 6B is a diagram illustrating state transition of the imaging system100 according to the embodiment. A state of S0 in FIG. 6B indicates apower OFF state and a reset state. A state of S1 indicates an idle statethat is a default state after releasing the reset state. At that time,the control register has a value of ‘BOO and is in a state where thetransfer is stopped.

A state of S2 indicates a state where the image reaches to the AE imagesensor 102B from the lens. In the state of S2, the data in the automaticexposer operation is transferred. A state of S3 is in a state where theimage reaches to the image capturing-image sensor 102A from the lens. Inthe state of S3, the data in the image capturing operation istransferred.

The state transitions from S1 to S2 when the control register is in thestate of ‘b01 (automatic control) or ‘b10 (two-pixel parallel transfermode (path for image capturing)). In the automatic control, the statetransitions to S2 again when the frame valid signal from the AE imagesensor 102B side is asserted (frame valid signal for imagecapturing=ON). The state further transitions to S3 when the frame validsignal from the AE image sensor 102B side is negated (frame valid signalfor image capturing=OFF) and the status signal 130 switches to the firststate (mirror=open).

The state transitions from S1 to S3 when the control register indicates‘b11 (two-line parallel transfer mode (path for AE)). Under theautomatic control, the state transitions to S3 again when the framevalid signal from the image capturing-image sensor 102A side is asserted(frame valid signal for AE=ON). The state further transitions to S2 whenthe frame valid signal from the image capturing-image sensor 102A sideis negated (frame valid signal for AE=OFF) and the status signal 130switches to the second state (mirror=close).

When the control register is not in the automatic control mode (‘b01),the transition between S2 and S3 is not automatically performed.

In the first embodiment described above, the image transfer modeselection circuit 116 is provided in the latter-stage of the selector114. However, the location of the image transfer mode selection circuit116 is not limited to the embodiment described above. For example, theimage transfer mode selection circuit may be placed in pre-stage of aselector as described below with reference to FIG. 7. FIG. 7 is a blockdiagram illustrating an imaging system 300 according to a secondembodiment. An image processing engine 308 illustrated in FIG. 7 has asimilar configuration to the image processing engine 108 according tothe first embodiment described above with reference to FIGS. 1 to 6, anddifferences between the first embodiment and the second embodiment aremainly described below. In FIG. 7, a numeral reference that has the samelast two digits with the numeral reference of a corresponding block inFIG. 1 is assigned to a block having the same function as thecorresponding block in FIG. 1.

The imaging system 300 illustrated in FIG. 7 includes a plurality ofimage sensors 302 (302A and 302B), an arithmetic processing device 304,and the image processing engine 308. In FIG. 7, a detailed configurationof the image processing engine 308 is further illustrated. The imageprocessing engine 308 illustrated in FIG. 7 includes a plurality ofinterface controllers 310 (310A and 310B) placed in an input side, aplurality of image processors 312 (312A and 312B), a selector 314, animage transfer mode selection circuit 316, and an interface controller318 placed in an output side. In the second embodiment, the twointerface controllers 310A and 310B and the two image processors 312Aand 312B are provided to correspond to the two image sensors 302A and302B.

The interface controllers 310A and 310B generate and transfer image dataand control signals to the image processors 312A and 312B, respectively.The image processors 312A and 312B process the image data received, forexample, encode the image data. The image processor 312A that is usedfor image capturing directly outputs the image data and the controlsignal to the selector 314. The image processor 312B that is used for AEoutputs the image data and the control signal to the selector 314 viathe image transfer mode selection circuit 316.

The image transfer mode selection circuit 316 selects a line-paralleltransfer mode from the AE image sensor 302B based on a status signal 330from the mirror mechanism 306. In the second embodiment, the imagetransfer mode selection circuit 316 generates a selection control signalthat activates a mode changing function when the status signal 330indicates that a side including the AE image sensor 302B is selected(status signal 330 indicates a second state (close)). The image transfermode selection circuit 316 then changes a transfer mode of the imagedata and the control signal, which are from the second side includingthe AE image sensor 302B, from a pixel-parallel transfer mode to aline-parallel transfer mode, and outputs the image data and the controlsignal in the changed transfer mode, which is the pixel-paralleltransfer mode, to the selector 314 placed in the latter-stage.

The selector 314 selects one of the image data and the control signaltransferred from the image capturing-image sensor 302A and the imagedata and the control signal transferred from the AE image sensor 302Bvia the image transfer mode selection circuit 316, and then outputs theselected image data and control signal to the interface controller 318placed in the latter-stage. In the second embodiment, the selector 314selects a data path that is from the interface controller 310A of animage capturing-image sensor 302A side to the interface controller 318,based on the status signal 330 from the mirror mechanism 306, whichindicates the selection of the image capturing-image sensor 302A side.At the same time, the selector 314 selects the data path that is fromthe interface controller 310B of the AE image sensor 302B side to theinterface controller 318, based on the status signal 130 from the mirrormechanism 306, which indicates the selection of the AE image sensor 302Bside.

As described above, the image data and the control signal aretransferred from the interface controllers 310A and 310B to theinterface controller 318. The interface controller 318 generates imagearea information based on the control signal input from the pre-stage.The interface controller 318 then outputs, in the pixel-paralleltransfer mode, the image data from the image capturing-image sensor 302Aor the image data of which the transfer mode is changed with the imagetransfer mode selection circuit 316 to the arithmetic processing device304 placed in the latter-stage through a differential serial bus.

The image transfer mode selection circuit 316 may be placed in thepre-stage of the selector 314 as described below with reference to FIG.7.

According to the embodiments as described above, the image processingapparatus, the imaging system, and the data transfer method can processthe plurality of lines at a time by transferring the plurality ofelements, namely pixels, each of which belongs to corresponding one ofthe plurality of lines, in parallel, and then output the plurality ofelements, namely the pixels, each of which belongs to the same line inparallel by changing the transfer mode according to the signals.

With the configurations of the embodiments, the transfer mode isautomatically changed using the status signal 130 from the outside,without involving the arithmetic processing device 104 such as inparticular a digital signal processor (DSP), and thus the image data canbe obtained with a high speed.

Here, terminologies of element and pixel are interchangeably used eachother. In addition to that, the transfer data and the image data areinterchangeably used each other. Additionally, as the signals indicatingthe selections, the status signal indicating a status of the mirrormechanism. The status of mirror mechanism indicates one of the imagesensors get an image. However this is not limited to the embodiments,and the transfer mode can be controlled to be changed based on otherstatus signal indicating a state of other part than mirror mechanism inanother embodiment. Additionally, the pixels and the image data may bereplaced other information elements and other data.

In the embodiments described below, the image processing engines 103 and308 are described as examples of an image processing device.

However, in other embodiments, the information processing devices may beany devices including still image photographing devices such as asingle-lens reflex camera and a digital single-lens camera that includesthe image processing engine 108 or 308, moving image capturing devicessuch as a video camera and a handy camera, image transferring devicessuch as a facsimile communication device, portable information terminalssuch as a smart phone and a tablet computer, versatile informationprocessing devices such as a personal computer, etc.

A part of the functions of the described embodiments or all functions ofthe described embodiments may be implemented by one or more processingcircuits. A processing circuit includes a programmed processor, as aprocessor includes circuitry. A processing circuit includes aprogrammable device (PD) such as a Field Programmable Gate Array (FPGA)for example. A processing circuit also includes devices such as anapplication specific integrated circuit (ASIC) and conventional circuitcomponents arranged to perform the recited functions. It is alsopossible to distribute them storing a recording medium as data describedin circuit configuration data (bit stream data) downloaded to the PD toimplement the functional blocks on the PD, Hardware Description Language(HDL) for generating the circuit configuration data, Very High speedintegrated circuits hardware Description Language (VHDL), andVerilog-HDL etc.

Although the exemplary embodiments of the disclosure have been describedand illustrated above, such description is not intended that thedisclosure be limited to the illustrated embodiments. Numerousadditional modifications and variations are possible in light of theabove teachings. It is therefore to be understood that within the scopeof the appended claims, the embodiments may be practiced otherwise thanas specifically described herein. For example, elements and/or featuresof different illustrative embodiments may be combined with each otherand/or substituted for each other within the scope of this disclosureand appended claims.

What is claimed is:
 1. An information processing device comprising: afirst input interface configured to receive data transferred in a firsttransfer mode in which a plurality of elements of the data eachbelonging to a same line of a plurality of lines are transferred inparallel; a second input interface configured to receive datatransferred in a second transfer mode in which a plurality of elementsof the data each belonging to a corresponding one of the plurality oflines are transferred in parallel; a mode selection circuit configuredto change a transfer mode of the data from the second input interfacefrom the second transfer mode to the first transfer mode based on asignal, the signal indicating selection of the second input interface;and an output interface configured to output one of the data from thefirst input interface and the data from the second input interface, thedata from the second input interface being output after the transfermode is changed to the first transfer mode.
 2. The informationprocessing device of claim 1, wherein the mode selection circuitcomprises: a setting circuit to set whether to change the transfer modewhen the signal indicating the selection of the second input interfaceis input.
 3. The information processing device of claim 1, wherein eachof the first input interface and the second input interface isconfigured to generate a timing control signal based on area informationinput to each of the first input interface and the second inputinterface, and the output interface is configured to generate areainformation based on the timing control signal input to the outputinterface from a pre-stage, the pre-stage including the first inputinterface and the second input interface.
 4. The information processingdevice of claim 2, wherein the timing control signal includes a framevalid signal, and when the mode selection circuit detects switching ofthe signal from the signal indicating the selection of the first inputinterface to the signal indicating the selection of the second inputinterface, the mode selection circuit is configured to control datatransfer of the data transferred from the second input interface to alatter-stage based on at least one of a state of the frame valid signalfrom the first input interface and a state of the frame valid signalfrom the second input interface.
 5. The information processing device ofclaim 2, wherein the timing control signal includes a linesynchronization signal, a frame valid signal, and a line valid signal,and the mode selection circuit comprising; a line buffer; a bufferconfigured to store each of the plurality of elements belonging to thecorresponding one of the plurality of lines of the data transferred fromthe second input interface to the line buffer, based on the linesynchronization signal, the frame valid signal, and the line validsignal from the second input interface; a signal generator configured tomeasure a cycle of the line synchronization signal from the second inputinterface and generate a pseudo line synchronization signal having apseudo line cycle based on the cycle measured; and a controllerconfigured to read the plurality of elements belonging to the same linestored in the line buffer based on the pseudo line synchronizationsignal and the frame valid signal synchronized with the pseudo linesynchronization signal and transfer the data from the second inputinterface with the line valid signal synchronized with the pseudo linesynchronization signal to a latter-stage.
 6. The information processingdevice of claim 5, wherein the first input interface, the second inputinterface, and the output interface each include a differential serialinterface, and the signal generator is configured to stop generating thepseudo line synchronization signal having the pseudo line cycle during aperiod in which the frame valid signal indicates a frame is invalid. 7.The information processing device of claim 2, further comprising: aselector configured to select one of a first data path and a second datapath, the first data path being from the first input interface to theoutput interface, the second data path being from the second inputinterface to the output interface, wherein the selector is configured toselect the first data path based on the signal indicating the selectionof the first input interface, and the selector is configured to selectthe second data path based on the signal indicating the selection of thesecond input interface.
 8. The information processing device of claim 6,wherein the timing control signal includes a frame valid signal, andwherein the selector is configured to control data transfer of the datatransferred from the second input interface to a latter-stage based onat least one of a state of the frame valid signal from the first inputinterface and a state of the frame valid signal from the second inputinterface, when detecting switching of the signal from the signalindicating the selection the first input interface to the signalindicating the selection of the second input interface.
 9. An imagingsystem comprising: the information processing device of claim 1; a firstimage sensor coupled to the first input interface of the imageprocessing device; a second image sensor coupled to the second inputinterface of the image processing device; an arithmetic processingdevice coupled to the output interface of the information processingdevice and configured to output a synchronization signal to each of thefirst image sensor and the second image sensor; and a mirror mechanismhaving a first state where image reaches the first image sensor and asecond state where the image reaches the second image sensor; andwherein the elements include pixels, the data includes image data, andthe signal indicating the selection of the second input interface is astatus signal indicating that the mirror mechanism is in the secondstate where the image reaches the second image sensor.
 10. Theinformation processing device of claim 1, wherein the first inputinterface is configured to receive the data from a first image sensor,the second input interface is configured to receive the data from asecond image sensor, the elements include pixels, the data includesimage data, and the signal indicating the selection of the second inputinterface is a status signal indicating that an external device is in astate where an image reaches the second image sensor.
 11. An informationprocessing device comprising: first means for inputting data transferredin a first transfer mode in which a plurality of elements of the dataeach belonging to a same line of a plurality of lines are transferred inparallel; second means for inputting data transferred in a secondtransfer mode in which a plurality of elements of the data eachbelonging to a corresponding one of the plurality of lines aretransferred in parallel; means for changing a transfer mode of the datafrom the second means for inputting from the second transfer mode to thefirst transfer mode based on a signal, the signal indicating selectionof the second means for inputting; and means for outputting data fromone of the first means for inputting and the second means for inputting,the data from the second means for inputting being output after thetransfer mode is changed to the first transfer mode.
 12. The informationprocessing device of claim 11, wherein the means for changing comprises:means for setting whether to change the transfer mode when the signalindicating the selection of the second means for inputting is input. 13.The information processing device of claim 11, wherein each of the firstmeans for inputting and the second means for inputting generates atiming control signal based on area information, and the means foroutputting generates area information based on the timing control signalinput from a pre-stage, the pre-stage including the first means forinputting and the second means for inputting.
 14. The informationprocessing device of claim 12, wherein the timing control signalincludes a frame valid signal, and when the means for changing detectsswitching of the signal from the signal indicating the selection of thefirst means for inputting to the signal indicating the selection of thesecond means for inputting, the means for changing controls datatransfer of the data transferred from the second means for inputting toa latter-stage, based on at least one of a state of the frame validsignal from the first means for inputting and a state of the frame validsignal from the second means for inputting.
 15. The informationprocessing device of claim 12, wherein the timing control signalincludes a line synchronization signal, a frame valid signal, and a linevalid signal, and the means for changing comprising: means for storingeach of the plurality of elements belonging to the corresponding one ofthe plurality of lines of the data transferred from the second means forinputting to the line buffer, based on the line synchronization signal,the frame valid signal, and the line valid signal from the second meansfor inputting; means for measuring a cycle of the line synchronizationsignal from the second means for inputting and generating a pseudo linesynchronization signal having a pseudo line cycle based on the cyclemeasured; and means for reading the plurality of elements belonging tothe same line stored in the line buffer based on the pseudo linesynchronization signal and the frame valid signal synchronized with thepseudo line synchronization signal and transferring the data from thesecond means for inputting with the line valid signal synchronized withthe pseudo line synchronization signal to a latter-stage.
 16. Theinformation processing device of claim 15, wherein the first means forinputting, the second means for inputting, and the means for outputtingincludes a differential serial interface, and means for generating stopsgenerating the pseudo line synchronization signal having the pseudo linecycle during a period in which the frame valid signal indicates a frameis invalid.
 17. The information processing device of claim 12 furthercomprising: means for selecting one of a first data path and a seconddata path, the first data path being from the first means for inputtingto the means for outputting, and the second data path being from thesecond means for inputting to the means for outputting, wherein themeans for selecting selects the first data path based on the signalindicating the selection of the first means for inputting, and the meansfor selecting selects the second data path based on the signalindicating the selection of the second means for inputting.
 18. Theinformation processing device of claim 16, wherein the timing controlsignal includes a frame valid signal, and wherein when the means forselecting detects switching of the signal from the signal indicating theselection of the first means for inputting to the signal indicating theselection of the second means for inputting, the means for selectingcontrols data transfer of the data transferred from the second means forinputting to a latter-stage, based on at least one of a state of theframe valid signal from the first means for inputting and a state of theframe valid signal from the second means for inputting.
 19. A method ofprocessing information performed by an information processing device,the information processing device including a first input interface, asecond input interface, and an output interface, the method comprising:inputting, at the first input interface, data transferred in a firsttransfer mode in which a plurality of elements of the data eachbelonging to a same line are transferred in parallel; and outputting, atthe output interface, the data transferred in the first transfer modebased on a signal, the signal indicating selection of the second inputinterface, inputting data transferred in a second transfer mode in whichthe plurality of elements each belonging to a corresponding one of aplurality of lines are transferred in parallel; changing a transfer modeof the data from the second transfer mode to the first transfer mode, inwhich the plurality of elements each belonging to the same line aretransferred in parallel; and outputting, at the output interface, thedata of which the transfer mode is changed from the second transfer modeto the first transfer mode.
 20. The method of claim 19, wherein thefirst input interface is configured to receive the data from a firstimage sensor, the second input interface is configured to receive thedata from a second image sensor, the elements include pixels, the dataincludes image data, and the signal indicating the selection of thesecond input interface is a status signal indicating that an externaldevice is in a state where an image reaches the second image sensor.